Various propeller-driven devices have been devised which can be attached to or installed in a small craft and which enable the user to propel the craft and at the same time to steer it. Some of these devices are propelled by a hand-driven crank while others are propelled by a bicycle-like foot pedal assembly.
Such a user-propelled craft is often used for fishing, where it is desirable to be able to keep at least one hand free at all times to attend to the fishing gear. It is also desirable to be able to troll and propel the boat in very shallow or weed-clogged water while retaining the maximum maneuverability and still engage in fishing. To accomplish such a result the propeller drive apparatus must be capable of being raised and lowered at will.
Steering of such craft is usually accomplished by mounting the propeller horizontally on a vertical shaft assembly which includes a vertically rotatable housing which enables pivoting of the propeller drive about a vertical axis so that the propeller can be pointed in the direction of desired thrust. Such a device is shown, for example, in U.S. Pat. No. 4,324,551 issued to Gurries on Apr. 13, 1982. In the Gurries device there is shown a bow-mounted hand-cranked cable-driven propeller drive. Being cable driven, it is believed that the crank can be turned in only one direction, since the cable will unwind, bind or break if the crank is turned in the opposite direction with a load at the other end of the cable drive. Steering of the craft is accomplished by a foot pedal-actuated steering cable which is wrapped around the upper portion of a propeller drive housing. The drive housing is enabled to rotate about a vertical axis. Further, in the Gurries device the propeller drive housing may be raised about a horizontal axis by actuating both steering foot pedals simultaneously and at the same time releasing a retaining pin on a catch bar. To lower the propeller drive such catch bar must be released by pulling on an attached string while again depressing both pedals simultaneously to allow the user to lower the propeller drive by gravity. Such a device is believed to be very awkward when a boat carrying it is attempted to be used for fishing purposes. Both hands and feet are occupied while propelling and raising and lowering the propeller, so that attention to the fishing gear cannot take place at such time. In addition, propeller cannot be simultaneously steered while it is being raised and lowered. Finally, when trying to lower the propeller drive a hand must be released from the hand crank mechanism to release the catch bar.
The ability to actuate a propeller drive by means of hand or foot pedals is shown in U.S. Pat. No. 3,010,421 issued to Perkins on Nov. 28, 1961. The Perkins propeller drive is adapted to be mounted on the stern or transom of a rowboat and cannot be raised or lowered while in operation.
Other foot-operated propeller-driven boat propulsion systems are shown in U.S. Pat. Nos. 2,703,065 issued to Gresham on Mar. 1, 1955; 3,211,125 issued to Yarbrough on Oct. 12, 1965; 4,891,024 issued to Benjamin on Jan. 2, 1990; and 4,427,392 issued to Schneider on Jan. 24, 1984.
The Gresham device is bolted to a boat and in order to raise the propeller drive a retaining hinge pin must be physically removed. Powered drive to the propeller in Gresham cannot take place when it is raised or lowered, and powered drive can only occur while the propeller drive is locked vertically, since rotation of Gresham's propeller drive shaft can only occur when a drive belt is fully extended and wrapped around drive sheaves.
The Yarbrough device also requires the physical removal of a drive pin to enable the lifting of the propeller out of the water. Steering cannot occur while the propeller is being raised or lowered in the water since a steering cable is used which will go slack when the pulley it is wrapped around is tilted along with the propeller drive shaft.
In the Benjamin device pivoting of the propeller drive shaft out of the water requires physically releasing a clamp, and steering is accomplished by means of a swivelled seat.
The Schneider device also requires that a hook be physically released to allow tilting upwards of the propeller driver shaft, and the actual tilting requires bodily grasping and moving the propeller drive assembly. In addition, in the Schneider device the operator faces rearwardly, thus necessitating continuous bodily turning movement to ascertain the direction of forward progress. Such an arrangement is believed to be inherently unsafe if there is only one occupant of the craft.
Still other boat drive and steering mechanisms are disclosed in U.S. Pat. Nos. 3,257,987 issued to Liard on Jun. 28, 1966; and 3,244,136 issued to Yarbrough on Apr. 5, 1966.